David Christian talks about the beginning of the universe. Here's an animation that does the same thing. How did the universe begin -- and how is it expanding? CERN physicist Tom Whyntie shows how cosmologists and particle physicists explore these questions by replicating the heat, energy, and activity of the first few seconds of our universe, from right after the Big Bang.

The Goldilocks principle states that something must fall within certain margins, as opposed to reaching extremes. When the effects of the principle are observed, it is known as the Goldilocks effect.

You know how it all started, but how do you think it's all going to end? The shape, contents and future of the universe are all intricately related. We know that it’s mostly flat; we know that it’s made up of baryonic matter (like stars and planets), but mostly dark matter and dark energy; and we know that it’s expanding constantly, so that all stars will eventually burn out into a cold nothingness. Renée Hlozek expands on the beauty of this dark ending.